<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
    <style>
      div p:last-child {
        color: red;
      }
    </style>
  </head>

  <body>
    <div>
      <p>你好1</p>
      <p>你好2</p>
    </div>
    <div>
      <p>你好1</p>
      <p>你好2</p>
    </div>
    <div>
      <p>你好1</p>
      <p>你好2</p>
    </div>
  </body>
</html>
